In December 2006, John O'Shea returned a rare goal for Manchester United which prompted an unprecedented celebration from the Red Devils. Influential centre back Rio Ferdinand assembled the United troops, dropped to their knees and Rio began a gesture that imitated aiming a rocket-launcher, taking sight and firing away.

When the media probed as to what the meaning of it was (British troops were deployed in Afghanistan and Iraq at the time), it turned out there was no political motive but, rather, something far more innocent.

The celebration was an in-joke between the Manchester United camp and the English players in the Chelsea camp as the Three Lions had become obsessed with the video game SOCOM 3: US Navy Seals. The game had been recommended to Rio by Chelsea captain John Terry.

While video game genres come and go depending on what is hot, there is one game that is a constant with footballers... and it is not anything to do with literal warfare, but rather FIFA, in whatever the latest incantation is.

But, regardless, there is still a virtual rivalry between Chelsea and United, as Terry's defensive partner Gary Cahill has revealed that not only are the entire roster of Blues regular players, but he also takes on one Liverpool star and one United star - but who is the best?

'We’re all into it,' confessed Cahill, as quoted by Shortlist when speaking on behalf of one of his sponsors, Rotary. 'I play it online against Danny Sturridge. He’s better than me. Wayne Rooney, too.